Method for checking an object made of transparent material and corresponding checking system

Method for checking the surface and/or shape of at least one surface, or part thereof, of an object made of transparent material, by means of a checking system which comprises a light source, a sensor and a processing unit connected to the sensor. By an appropriate positioning of the light source and sensor it is possible to overcome the problem of multiple reflections and to identify in a unique manner the rays scattered from the surface to be checked and received by the sensor which are useful for the purposes of checking. According to one of the embodiments, it is also possible to determine the thickness of the object to be checked.